path: root/man/tip/nng_ctx_setopt.3.html

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version: tip
layout: manpage_v2
title: nng_ctx_setopt(3)
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<h1>nng_ctx_setopt(3)</h1>
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<h2 id="_name">NAME</h2>
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<div class="paragraph">
<p>nng_ctx_setopt - set context option</p>
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<h2 id="_synopsis">SYNOPSIS</h2>
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<pre class="pygments highlight"><code data-lang="c"><span></span><span class="tok-cp">#include</span><span class="tok-w"> </span><span class="tok-cpf">&lt;nng/nng.h&gt;</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">void</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">val</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-kt">size_t</span><span class="tok-w"> </span><span class="tok-n">valsz</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_bool</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-n">bval</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_int</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-n">ival</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_ms</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-n">nng_duration</span><span class="tok-w"> </span><span class="tok-n">dur</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_size</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-kt">size_t</span><span class="tok-w"> </span><span class="tok-n">z</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_string</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">str</span><span class="tok-p">);</span>

<span class="tok-kt">int</span><span class="tok-w"> </span><span class="tok-nf">nng_ctx_setopt_uint64</span><span class="tok-p">(</span><span class="tok-n">nng_ctx</span><span class="tok-w"> </span><span class="tok-n">ctx</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-k">const</span><span class="tok-w"> </span><span class="tok-kt">char</span><span class="tok-w"> </span><span class="tok-o">*</span><span class="tok-n">opt</span><span class="tok-p">,</span><span class="tok-w"> </span><span class="tok-kt">uint64_t</span><span class="tok-w"> </span><span class="tok-n">u64</span><span class="tok-p">);</span></code></pre>
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<h2 id="_description">DESCRIPTION</h2>
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<i class="fa icon-important" title="Important"></i>
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These functions are deprecated.  Please see <a href="nng_ctx_set.3.html">nng_ctx_set</a>.
They may not be present if the library was built with <code>NNG_ELIDE_DEPRECATED</code>.
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<p>
The <code>nng_ctx_setopt()</code> functions are used to configure options for
the context <em>ctx</em>.
The actual options that may be configured in this way vary, and are
specified by <em>opt</em>.</p>
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<i class="fa icon-note" title="Note"></i>
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Context options are protocol specific.
The details will be documented with the protocol.
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<h3 id="_forms">Forms</h3>
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<p>The details of the type, size, and semantics of the option will depend
on the actual option, and will be documented with the option itself.</p>
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<dl>
<dt class="hdlist1"><code>nng_ctx_setopt()</code></dt>
<dd>
<p>This function is untyped, and can be used to configure any arbitrary data.
The <em>val</em> pointer addresses the data to copy, and <em>valsz</em> is the
size of the objected located at <em>val</em>.</p>
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</dl>
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<i class="fa icon-tip" title="Tip"></i>
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It may be easier to use one of the typed forms of this function.
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<dt class="hdlist1"><code>nng_ctx_setopt_bool()</code></dt>
<dd>
<p>This function is for options which take a Boolean (<code>bool</code>).
The <em>bval</em> is passed to the option.</p>
</dd>
<dt class="hdlist1"><code>nng_ctx_setopt_int()</code></dt>
<dd>
<p>This function is for options which take an integer (<code>int</code>).
The <em>ival</em> is passed to the option.</p>
</dd>
<dt class="hdlist1"><code>nng_ctx_setopt_ms()</code></dt>
<dd>
<p>This function is used to configure time durations (such as timeouts) using
type <a href="nng_duration.5.html"><code>nng_duration</code></a>.
The duration <em>dur</em> is an integer number of milliseconds.</p>
</dd>
<dt class="hdlist1"><code>nng_ctx_setopt_size()</code></dt>
<dd>
<p>This function is used to configure a size, <em>z</em>, typically for buffer sizes,
message maximum sizes, and similar options.</p>
</dd>
<dt class="hdlist1"><code>nng_ctx_setopt_string()</code></dt>
<dd>
<p>This function is used to pass configure a string, <em>str</em>.
Strings passed this way must be legal UTF-8 or ASCII strings, terminated
with a <code>NUL</code> (<code>\0</code>) byte.
(Other constraints may apply as well, see the documentation for each option
for details.)</p>
</dd>
<dt class="hdlist1"><code>nng_ctx_setopt_uint64()</code></dt>
<dd>
<p>This function is used to configure a 64-bit unsigned value, <em>u64</em>.
This is typically used for options related to identifiers, network numbers,
and similar.</p>
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<h2 id="_return_values">RETURN VALUES</h2>
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<p>These functions return 0 on success, and non-zero otherwise.</p>
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<h2 id="_errors">ERRORS</h2>
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<code>NNG_ECLOSED</code>
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<p>Parameter <em>s</em> does not refer to an open socket.</p>
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<code>NNG_EINVAL</code>
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<p>The value being passed is invalid.</p>
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<code>NNG_ENOTSUP</code>
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<p>The option <em>opt</em> is not supported.</p>
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<code>NNG_EREADONLY</code>
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<p>The option <em>opt</em> is read-only.</p>
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<code>NNG_ESTATE</code>
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<p>The socket is in an inappropriate state for setting this option.</p>
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<h2 id="_see_also">SEE ALSO</h2>
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<div class="paragraph text-left">
<p><a href="nng_ctx_getopt.3.html">nng_ctx_getopt(3)</a>,
<a href="nng_setopt.3.html">nng_setopt(3)</a>,
<a href="nng_strerror.3.html">nng_strerror(3)</a>,
<a href="nng_ctx.5.html">nng_ctx(5)</a>,
<a href="nng_options.5.html">nng_options(5)</a>,
<a href="nng_socket.5.html">nng_socket(5)</a>,
<a href="nng.7.html">nng(7)</a></p>
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